refactor: unexport internal identifiers and fix naming nits

cmd/root.go

@@ -15,7 +15,7 @@ import (
 const updateNoticeAnnotation = "godeez:update-notice"
 
 func Execute(ctx context.Context) error {
-	root := NewRootCmd()
+	root := newRootCmd()
 
 	var notice <-chan string
 	if wantsUpdateNotice(root) {
@@ -29,7 +29,7 @@ func Execute(ctx context.Context) error {
 	return err
 }
 
-func NewRootCmd() *cobra.Command {
+func newRootCmd() *cobra.Command {
 	root := &cobra.Command{
 		Use:          "godeez",
 		Short:        "GoDeez is a tool to download music from Deezer",

internal/deezer/blowfish_test.go

@@ -51,6 +51,6 @@ func TestDecryptBlowfishRoundTrip(t *testing.T) {
 
 func TestDecryptBlowfishInvalidKey(t *testing.T) {
 	if _, err := DecryptBlowfish(make([]byte, 8), nil); err == nil {
-		t.Error("expected error for empty key")
+		t.Error("expected error for nil key")
 	}
 }

internal/deezer/client.go

@@ -78,7 +78,7 @@ func (c *Client) FetchResource(ctx context.Context, kind Kind, id string) (Resou
 		return nil, err
 	}
 
-	url := fmt.Sprintf("https://www.deezer.com/ajax/gw-light.php?method=deezer.page%s&input=3&api_version=1.0&api_token=%s", kind.pageMethod(), c.Session.APIToken)
+	url := fmt.Sprintf("https://www.deezer.com/ajax/gw-light.php?method=deezer.page%s&input=3&api_version=1.0&api_token=%s", kind.pageMethod(), c.Session.apiToken)
 	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewBuffer(jsonData))
 	if err != nil {
 		return nil, err
@@ -132,7 +132,7 @@ func (c *Client) FetchMedia(ctx context.Context, track *Track, quality string) (
 		"flac":    `[{"cipher":"BF_CBC_STRIPE","format":"FLAC"},{"cipher":"BF_CBC_STRIPE","format":"MP3_320"},{"cipher":"BF_CBC_STRIPE","format":"MP3_128"}]`,
 	}
 
-	reqBody := fmt.Sprintf(`{"license_token":"%s","media":[{"type":"FULL","formats":%s}],"track_tokens":["%s"]}`, c.Session.LicenseToken, qualityFormats[quality], track.TrackToken)
+	reqBody := fmt.Sprintf(`{"license_token":"%s","media":[{"type":"FULL","formats":%s}],"track_tokens":["%s"]}`, c.Session.licenseToken, qualityFormats[quality], track.TrackToken)
 	req, err := http.NewRequestWithContext(ctx, http.MethodPost, "https://media.deezer.com/v1/get_url", bytes.NewBuffer([]byte(reqBody)))
 	if err != nil {
 		return nil, err

internal/deezer/credentials.go

@@ -19,7 +19,7 @@ type Credentials struct {
 	ARL      string `json:"arl,omitempty"`
 }
 
-func LoadCredentials() (*Credentials, error) {
+func loadCredentials() (*Credentials, error) {
 	secret, err := keyring.Get(keyringService, keyringUser)
 	if err != nil {
 		if errors.Is(err, keyring.ErrNotFound) {
@@ -36,7 +36,7 @@ func LoadCredentials() (*Credentials, error) {
 	return &creds, nil
 }
 
-func SaveCredentials(creds *Credentials) error {
+func saveCredentials(creds *Credentials) error {
 	data, err := json.Marshal(creds)
 	if err != nil {
 		return err

internal/deezer/login.go

@@ -7,7 +7,7 @@ import (
 )
 
 func resolveARL(ctx context.Context, validate func(ctx context.Context, arl string) error) (string, error) {
-	creds, err := LoadCredentials()
+	creds, err := loadCredentials()
 	if err != nil {
 		return "", err
 	}
@@ -46,7 +46,7 @@ func Login(ctx context.Context, email, password string) (string, string, error)
 		return "", "", err
 	}
 
-	if err := SaveCredentials(creds); err != nil {
+	if err := saveCredentials(creds); err != nil {
 		return "", "", err
 	}
 

internal/deezer/session.go

@@ -14,8 +14,8 @@ import (
 var ErrInvalidARL = errors.New("invalid or expired ARL cookie")
 
 type Session struct {
-	APIToken     string
+	apiToken     string
-	LicenseToken string
+	licenseToken string
 	HTTPClient   *http.Client
 	Premium      bool
 }
@@ -79,8 +79,8 @@ func authenticate(ctx context.Context, arlCookie string) (*Session, error) {
 
 	opts := res.Results.User.Options
 	return &Session{
-		APIToken:     res.Results.APIToken,
+		apiToken:     res.Results.APIToken,
-		LicenseToken: opts.LicenseToken,
+		licenseToken: opts.LicenseToken,
 		HTTPClient:   client,
 		Premium:      opts.MobileOffline || opts.WebOffline,
 	}, nil

internal/deezer/track.go

@@ -69,17 +69,17 @@ func (t *Track) Filename(kind Kind, mediaFormat string) string {
 	return base + "." + ext
 }
 
-func truncateBytes(s string, max int) string {
+func truncateBytes(s string, maxLen int) string {
-	if max <= 0 {
+	if maxLen <= 0 {
 		return ""
 	}
-	if len(s) <= max {
+	if len(s) <= maxLen {
 		return s
 	}
 
 	last := 0
 	for i := range s {
-		if i > max {
+		if i > maxLen {
 			return s[:last]
 		}
 		last = i

internal/download/bpm.go

@@ -7,7 +7,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
-	neturl "net/url"
+	"net/url"
 	"regexp"
 	"strconv"
 	"strings"
@@ -38,7 +38,7 @@ func fetchBPM(ctx context.Context, httpClient *http.Client, artist, title, durat
 func findTrackURL(ctx context.Context, httpClient *http.Client, artist, title, duration string) (string, error) {
 	const rootURL = "https://songbpm.com"
 
-	values := neturl.Values{}
+	values := url.Values{}
 	values.Add("query", fmt.Sprintf("%s %s", artist, title))
 
 	req, err := http.NewRequestWithContext(ctx, http.MethodPost, rootURL+"/searches", bytes.NewBufferString(values.Encode()))
@@ -109,8 +109,8 @@ func findTrackURL(ctx context.Context, httpClient *http.Client, artist, title, d
 	return rootURL + matchURL, nil
 }
 
-func fetchBPMPage(ctx context.Context, httpClient *http.Client, url string) (string, error) {
+func fetchBPMPage(ctx context.Context, httpClient *http.Client, pageURL string) (string, error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, pageURL, nil)
 	if err != nil {
 		return "", err
 	}

internal/download/genre.go

@@ -57,8 +57,8 @@ func fetchGenre(ctx context.Context, httpClient *http.Client, artist, title stri
 	return formatTags(filtered), nil
 }
 
-func fetchGenrePage(ctx context.Context, httpClient *http.Client, url string) (*goquery.Document, error) {
+func fetchGenrePage(ctx context.Context, httpClient *http.Client, pageURL string) (*goquery.Document, error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, pageURL, nil)
 	if err != nil {
 		return nil, err
 	}

internal/download/metadata.go

@@ -20,7 +20,7 @@ type metadataResult struct {
 	warnings []string
 }
 
-func fetchMetadata(httpClient *http.Client, ctx context.Context, track *deezer.Track, opts Options) metadataResult {
+func fetchMetadata(ctx context.Context, httpClient *http.Client, track *deezer.Track, opts Options) metadataResult {
 	if !opts.BPM && !opts.Genre {
 		return metadataResult{}
 	}

internal/download/track.go

@@ -31,7 +31,7 @@ func (d *Downloader) downloadTrack(ctx context.Context, resource deezer.Resource
 
 	metadataChan := make(chan metadataResult, 1)
 	go func() {
-		metadataChan <- fetchMetadata(d.deezerClient.Session.HTTPClient, ctx, track, opts)
+		metadataChan <- fetchMetadata(ctx, d.deezerClient.Session.HTTPClient, track, opts)
 	}()
 
 	dlCtx, cancel := context.WithTimeout(ctx, opts.Timeout)

internal/update/apply.go

@@ -27,7 +27,7 @@ var managedPrefixes = []string{
 
 func resolveTarget() (string, error) {
 	if buildinfo.IsDev() {
-		return "", fmt.Errorf("development build cannot self-update. Install a release from https://github.com/%s/%s/releases",
+		return "", fmt.Errorf("development build cannot self-update; install a release from https://github.com/%s/%s/releases",
 			repoOwner, repoName)
 	}
 
@@ -43,7 +43,7 @@ func resolveTarget() (string, error) {
 
 	for _, prefix := range managedPrefixes {
 		if target == prefix || strings.HasPrefix(target, prefix+"/") {
-			return "", fmt.Errorf("%s was installed by a package manager. Update it with that instead", target)
+			return "", fmt.Errorf("%s was installed by a package manager; update it with that instead", target)
 		}
 	}
 
@@ -59,12 +59,12 @@ func CheckUpdatable() error {
 func checkWritable(dir string) error {
 	f, err := os.CreateTemp(dir, tmpPattern)
 	if err != nil {
-		hint := "Re-run with sudo"
+		hint := "re-run with sudo"
 		if runtime.GOOS == "windows" {
-			hint = "Re-run from an elevated prompt"
+			hint = "re-run from an elevated prompt"
 		}
 
-		return fmt.Errorf("cannot write to %s: %w. %s", dir, err, hint)
+		return fmt.Errorf("cannot write to %s: %w; %s", dir, err, hint)
 	}
 
 	name := f.Name()
@@ -198,7 +198,7 @@ func (u *Updater) replaceBinary(target, tmp string) error {
 
 	if err := os.Rename(tmp, target); err != nil {
 		if rollbackErr := os.Rename(old, target); rollbackErr != nil {
-			return fmt.Errorf("failed to install the new binary: %w. The previous one could not be restored from %s: %v",
+			return fmt.Errorf("failed to install the new binary: %w; the previous one could not be restored from %s: %v",
 				err, old, rollbackErr)
 		}
 

internal/update/check.go

@@ -73,7 +73,7 @@ func writeCache(version string) error {
 
 func check(ctx context.Context) (string, error) {
 	if entry, ok := readCache(); ok {
-		return newerThanCurrent(entry.LatestVersion), nil
+		return latestIfNewer(entry.LatestVersion), nil
 	}
 
 	release, err := New().Latest(ctx)
@@ -84,10 +84,10 @@ func check(ctx context.Context) (string, error) {
 	latest := release.Version()
 	_ = writeCache(latest)
 
-	return newerThanCurrent(latest), nil
+	return latestIfNewer(latest), nil
 }
 
-func newerThanCurrent(latest string) string {
+func latestIfNewer(latest string) string {
 	if IsNewer(buildinfo.Version(), latest) {
 		return latest
 	}